Phase change materials use the latent heat property of material to store thermal energy and can be used in methods of controlling temperature. Phase change materials are either organic such as paraffin or non-paraffin compounds, inorganic (salt hydrates and metallics) or eutectic (organic-organic, organic-inorganic, inorganic-inorganic). Despite the wide variety of available phase change materials, the following drawbacks may exist dependent upon the phase change material chosen:                relatively low density which limits the energy stored in a given volume;        relatively expensive and/or difficult to process;        inappropriate phase change temperatures;        inadequate storage of energy;        inappropriate corrosive effects;        irreversible segregation during phase changes;        low conductivity limiting the rate of melting and cooling, or the thickness of;        partial phase changes in a pack of certain sizes i.e. due to the conductivity, size and material choices portions of a pack may not change phase which limits the size of an optimal PCM pack;        suffer from super cooling;        are flammable.        
The following prior art documents are acknowledged: JP200080358, EP1837617, JP2005330484, U.S. 2008318050, CN101289611, CN101074854, EP1837385, and KR20060047958. The following prior art documents have also been identified: U.S. 2006/0185817, EP1947404, EP1455156, EP1739376, EP1455155, DE20314018 and DE20310593.